bgpd: aggr summary-only suppressed export to evpn

bgpd: aggr summary-only suppressed export to evpn

When exporting bgp vrf instance unicast route into
EVPN as type-5, check for suppressed ones and do not
export them.

Ticket:#3534718
Testing Done:

Config:

router bgp 660000 vrf vrf1
 bgp router-id 144.1.1.2
 no bgp network import-check
 neighbor 144.1.1.1 remote-as external
 !
 address-family ipv4 unicast
  aggregate-address 50.1.0.0/16 summary-only
  redistribute connected
 exit-address-family
 !
 address-family l2vpn evpn
  advertise ipv4 unicast
 exit-address-family
exit

v4 suppressed route: (5 suppressed routes not exported to evpn)

tor1# vtysh -c "show bgp vrf vrf1 ipv4 unicast" | grep "50.1"
*> 50.1.0.0/16      0.0.0.0(bordertor-11)
s> 50.1.1.212/32    6.0.0.30(leaf-11)<
s> 50.1.1.222/32    6.0.0.31(leaf-11)<
s> 50.1.110.0/24    0.0.0.0(bordertor-11)
s> 50.1.210.214/32  6.0.0.30(leaf-11)<
s> 50.1.220.224/32  6.0.0.31(leaf-11)<

tor1# vtysh -c "show bgp l2vpn evpn route" | grep -A3 "*> \[5\].*\[50.1"
*> [5]:[0]:[16]:[50.1.0.0] RD 144.1.1.2:7
                    6.0.0.1 (bordertor-11)
                                             0         32768 ?
                    ET:8 RT:4640:104001 Rmac:00:02:00:00:00:04

Signed-off-by: Chirag Shah <chirag@nvidia.com>
(cherry picked from commit 71d08ecc9d2a43997fe92193c3bd1d1203fa6954)